How computer/PLC memory and storage work
Growing up in the late 90s and early 2000s, it wasn’t unusual to hear old-timers refer to memory as “black magic.” That is, they would simply write storage and memory off as something computers did just to work. However, as computer scientists, we need to be a little more diligent and understand how memory devices work. To begin the discussion we’re going to explore how older, yet widely used, storage devices, hard disk drives (HDDs), work.
HDDs
HDDs once ruled the world of computer storage. HDDs could hold copious amounts of data and, for the most part, were reliable. HDDs were common in servers and personal computers for many years but eventually gave way to solid-state drives (SSDs).
HDDs could best be thought of as really large and reliable CDs. To summarize, the device works by magnetically encoding data to a disk, or as it is formally called, the platter. The platter is divided up into tiny subsections...
